Person of Interest

Season 4

Panopticon

1. The word 'Panopticon' loosely translated, means 'observe' (-opticon) 'all' (pan-). It is derived from the name 'Panoptes' in Greek mythology, a giant with a hundred eyes, who was known to be a highly effective watchman.
2. When Samaritan's face/voice recognition systems identify Senator Garrison, the following data is displayed: "Transgressions: Official Misconduct: 81 counts // Bribe Receivings: 661 counts // Conspiracy to Subvert the Constitution: 21 counts // Abuse of Alcohol: 124 events"
3. The term 'Panopticon' was coined in the late 1700s by the English philosopher and social theorist Jeremy Bentham for his concept for an institution where a single watchman is able to observe all the inmates without them being able to tell whether or not they are being watched.
4. The crime scene with Reese and Fusco shot on the roof was the first scene of the season. It was an extremely hot day, making production uncomfortable for all concerned.
5. Harold's new alias "Professor Whistler" is another bird name. Whistler is also the last name of Hugh Whistler, an English ornithologist.
6. First appearance of Martine Rousseau who would appear several times throughout the rest of the season. Several years before Cara Buono had appeared in Law and Order along with Michael Emerson, where his character was trying to kill Buono's character.
7. During one take of the scene under the bridge, an NYPD police helicopter began circling near the bridge. The director rolled cameras, but they were unable to use the footage.
8. The Machine places typographical errors in Finch's dissertation that lead him to the tunnels of the Interborough Rapid Transit (IRT) Company, the first operating subway system in New York, now part of the New York subway system. The IRT began service in 1904 as a private company, and operated until 1940, when it was purchased by the City of New York. Its lines are identifiable as the numbered lines on the modern New York subway system.
9. Following the bombing attempt, Reese recognizes that Ali has specialized military training, and identifies him as a member of Egypt's Unit 777. Unit 777 is a counter-terrorism and special operations unit, founded by Anwar Sadat's government in the late 1970s as part of Sadat's efforts to gain peace with Israel. The unit acts principally on threats occurring on Egyptian soil, but has been dispatched to international incidents as well. They train with units including the U.S. Army Delta Force and U.S. Navy SEALS.
10. Ali is able to build a mesh network by linking a series of routers, and broadcasting the signal across disused VHF television antennas. A mesh network is a routing technique where phone calls and messages travel by hopping from router to router within the network area. These small routers behave similarly to a home wireless router where one node is physically wired to an Internet connection, which is transmitted to other nodes in its vicinity. The network can be expanded simply by adding more nodes. All telecommunications, such as cell phones, are sent via Voice Over Internet Protocol (VoIP). Mesh networking is known for its simplicity, reliability and ease of use. In their commentary for the episode, writers Erik Mountain and Greg Plageman noted that this method of communication was used by protesters during the Arab Spring, notably in Egypt and Tunisia.
11. Reese sits at Carter's old desk after being promoted to Homicide.

Nautilus

1. The dog on the lost-dog poster is Michael Emerson's in real life, Chumley.
2. The "game" Claire is playing is a reference to web-hunt Cicada 3301.
3. The graffiti mural at the beginning of the episode was painted by New York artist Apache Gonzalez. The actual location of the mural is W 137th St by 7th Avenue in Harlem, not W 118th and Lenox, as displayed on Finch's phone.
4. Among the pivotal sites in the Nautilus game is 30 Rockefeller Center, often known as "30 Rock", the headquarters of the National Broadcasting Company (NBC). The building is famous for its ice skating rink and Christmas festivities, the NBC studios tour, and its observation deck, "The Top of the Rock" where Finch and Claire have their final meeting.
5. The biker bar is a real bar in east New York. The patches on the wall which give Claire her next clue were created by prop master Ruth DiPasswuale

Wingman

1. Shaw refers to a diet of "ramen and Two Buck Chuck". Two Buck Chuck is a range of inexpensive wine sold by California-based Trader Joe's Markets under the Charles Shaw label. The nickname refers to the $1.99/bottle price for the wine, which is made in bulk in California's Central Valley wine growing region.
2. Fusco mentioned that he broke up with Rhonda - his date in "Til Death".
3. Captain Moreno complains the precinct's CompStat numbers are down. CompStat is the NYPD's internal accountability system, which uses multiple sources of data to evaluate the efficacy of the NYPD.
4. In interviews relating to the episode, Jonathan Nolan commented on the need for an occasional lighter episode, such as this, designed to give the audience a break during a period of heavier story-telling.
5. This episode is the first in Machine POV since Samaritan came online. Unlike the first two episodes, the Machine is once again sending numbers to Finch.
6. Shaw wears a little black dress by Diane von Fuerstenberg and "Tayler" d'Orsay heels by Manolo Blahnik.
7. The bus Reese boards in the opening sequence is a hop-on/hop-off tour bus run by one of several tour companies. These busses are common in large cities with significant numbers of tourists. The scene on the bus was filmed in front of Bergdorf Goodman, a high-end department store on Fifth Avenue in Manhattan.
8. Reese comments his access to police video is, "Thanks to Big Brother." This is another reference to the surveillance state; in this case, to the all seeing Hitleresque Big Brother from the George Orwell novel Nineteen Eighty-Four.
9. Finch's alias "Mr. Egret" is another bird name.

Brotherhood

Prophets

1. The scenes with Root and Martine Rousseau shooting through the ceiling were filmed at Roosevelt Hotel on August 22, 2014.
2. The Burmese cat on the picture is actress Wrenn Schmidt's own.
3. Finch's reporter alias, Harold Cardinal, is another bird name.

Pretenders

1. At the 16'30" mark, Harold and Beth Bridges each name their favorite equations. Harold chooses the Pythagorean Identity which is the commonly known c^2 = a^2 + b^2 (c squared = a squared + b squared). Ms. Bridges chooses Euler's Identity, which is a formula in complex analysis: e to the power i times pi + 1 = 0. Both are considered important formulas in the fields of mathematics.
2. Harold gets Bear to eat his breakfast with the command "Eet je ontbijt", which is Dutch for "Eat your breakfast".

Honor Among Thieves

1. Marburg virus (MARV) is the cause of Marburg virus disease, a deadly form of hemorrhagic fever virtually indistinguishable from Ebola virus disease. The disease begins with fever and rash, and can result in multiple organ failure and death within 8-15 days.
2. Tomas uses lock manipulation to open the vault. This technique was also used by Graham Wyler in "The High Road". It represents safe cracking at its purest form because it does not damage the safe surface; instead it requires patience and a good ear to manipulate the lock into revealing the combination. In "The High Road", Finch calls this technique "a lost art".
3. In the opening scene, when Shaw is on her phone watching the stopwatch, you can see that the phone case is Magpul, a firearms manufacturer. Showing her character's continuing love of weapons.
4. While undercover and being interviewed for her job as an international thief, Shaw references working for McCauley's crew out of L.A., which is Robert De Niro's character's name in Heat (1995).

Point of Origin

1. Towards the end of the episode, Dominic draws a circle on a chalkboard and then quotes a math teacher he had who once said, "All the world's infinite possibilities rest within this one simple circle." Dominic then adds, "Including the possibility that the big, quiet kid in the back of the class, the one that everyone always underestimated, could one day run the streets of New York." During season 2 episode 11 (2Pi R), Finch posed as a substitute math teacher and, after drawing a circle and the symbol for Pi on the chalkboard, he's asked by a student what math is good for. He explains that Pi includes every number in existence and that, were those numbers converted into letters, every word in every possible combination would be contained within it. He ends his explanation with, "Everything we ever say or do, all of the world's infinite possibilities rest within this one simple circle. Now what you do with that information, what it's good for, well, that would be up to you." It is unlikely Dominic would have been in Finch's classroom that day as he is too old and knows too much to have been a high school student at the time.
2. The swimming pool scene was filmed at the same location as Swimfan
3. Shaw's ride is a '66 or '67 Pontiac GTO.

The Devil You Know

1. Elias' safe combination, 10 30 74 alludes to October 30, 1974, the day of the boxing match between George Foreman and Muhammad Ali. Foreman, at that time undefeated world heavyweight champion was defeated by Ali just before the end of the eighth round, with Ali employing his "rope-a-dope" strategy (which Reese references) . The event became known as The Rumble in the Jungle. Earlier in the episode, a photograph of the fight between George Foreman and Michael Moorer is shown hanging on the wall at the restaurant where Elias meets Gino.
2. Fusco refers to Root and Shaw as "Lucy and Ethel". Lucille Ricardo and Ethel Mertz, a pair of housewives inclined to find themselves in the middle of comic adventures, are the two main female characters in the 1950s CBS sitcom "I Love Lucy".
3. Elias's quote, "Sun Tzu would be impressed." acknowledging Dominic's strategy of studying his enemy and finding out their greatest weakness refers to Sun Tzu, a 5th-century BC Chinese general and strategist, and author of "The Art of War". Considered one of the seminal studies of military tactics and strategy, it has influenced western military procedures into contemporary times. First translated into English in 1905, it has been translated multiple times and studied widely by both military and non-military strategists. Both Sun Tzu and "The Art of War" were heavily referenced in "Wolf and Cub".
4. Elias and Anthony demonstrate a knowledge of some Latin. They are both Italian; Latin is very similar to Italian which derived from it.
5. There were two Latin phrases used: "Invictus maneo" means "I remain unvanquished"; "Morior Invictus" means "I die unvanquished".
6. The episode ends with Elias walking alone along the boardwalk of Brighton Beach. This is a nod to the character's first appearance in Episode 0107 "Witness", where Elias declares "veni vidi vici" as he victoriously struts with his Capo regime. As a direct contradiction, at the end of this episode, Elias declares "invictus maneo" as he stands alone against his new enemies.
7. Scarface and Elias both use Latin to send messages: Scarface: morior invictus Death before defeat (literally: "I die undefeated") Elias: invictus maneo I remain undefeated or I remain unvanquished
8. Dominic (the Brotherhood) refers to a high school teacher who taught him everything a person needed to know was contained in a circle. In Season 2, Finch played a high school teacher and taught his disengaged students about how the Pi circle included everything a person needed to know, all infinite possibilities. So it would be fair to assume Dominic's teacher and Finch - who played a high school teacher - are one and the same and that Dominic had once been one of Finch's students.

The Cold War

1. The team's new base of operations, an abandoned subway station, is hidden from access by a vending machine across the entrance. When Finch arrives he inserts a coin and then types the code 3141; the first four digits of Pi, a favourite number of Harold's.
2. Beatrice Lillie was a comic actress active from the 1920s to the mid-60s. Her final role was in the 1967 film Thoroughly Modern Millie, where she played the house mother at a women's rooming house who is actually the leader of a white slavery ring based in New York's Chinatown, thus the name of the sandwich.

If-Then-Else

1. This is the highest rated episode in the entire series.
2. Finch is using an actual software bug called Shellshock to gain access to the computer system. Shellshock is a family of security bugs in the widely used Unix Bash shell, first disclosed on 24 September 2014.
3. All super slow motion scenes were filmed with a Weiss camera, also used to film the opening credits.
4. This is the first episode in which the Machine explicitly identifies Fusco as an asset. He is identified as a secondary asset in the third simulation, when the probability of his survival is calculated.
5. Scenes in the basement of the stock exchange were filmed in an actual government server farm in Staten Island.
6. The command Finch asks Fusco to enter is most likely env x='() { :;}; echo vulnerable' bash -c "echo this is a test", a command used to check if a computer system is vulnerable to shellshock, a software bug which allows a user unauthorized access to a server.
7. The drawing in the episode is "Dancer Adjusting Her Slipper" by Edgar Degas (1873). Between 1873 and 1874, Degas made a series of pencil, chalk and graphite studies of ballet dancers, shown in different poses and from different angles. These drawings served as preparatory studies for his ballet themed paintings of the same period.
8. The opening scene with Finch and Root was filmed around 11 Broadway, close to the actual New York Stock Exchange.
9. The episode title, "If-Then-Else", is a reference to the decision branching commands in most computer programming languages.

Control-Alt-Delete

1. This episode principally follows Control, and the deployed ISA operatives Crimson 6, while the team is seen from Control's point of view. This is the second episode to break from the traditional formula, the first being Relevance in the second season, which introduced Shaw.
2. The President of the United States is referred to as POTUS. POTUS is a short-hand code-name for the President, which was popularized in the 1999-2006 television series The West Wing. The President, Vice President, their families and other key highly placed U.S. governmental officials have closely guarded call names used by the Secret Service to identify them. POTUS and FLOTUS (first lady), among others, have become the generic versions of these call names.
3. Mike Richelli, the White House Chief of Staff is introduced. The White House Chief of Staff answers directly to the President, and is the highest ranking political appointee in the U.S. The White House Chief of Staff has a range of responsibilities that vary from administration to administration, but principal among them are overseeing the White House staff, managing the President's schedule, controlling access to the President, serving as a Presidential advisor and confidante, and at times, informally representing the President. The White House Chief of Staff wields tremendous power, often second only to the President.
4. Fusco tells the tech monitoring Grice and Brooks that, "the Red Wings suck!" The Detroit Red Wings are one of the six original National Hockey League teams.

M.I.A.

1. The message Harold Finch (Michael Emerson) wrote down at the end of this episode: "Sierra Tango Oscar Papa". In other words, "Stop" using the "ICAO Phonetic Alphabet".
2. Scenes in Maple, NY were filmed in the towns of Tappan and Piermont, both located in Rockland County, New York.
3. Root refers to Shaw's situation as Schrödinger's cat. Schrödinger's cat is a paradoxical logic problem: when does a cat, locked in a box with a device that will eventually kill it, definitively become either dead or alive? Drawn from quantum mechanics, the study of quantities that can change only so much, and no more, it was initially applied to the physical state of matter. In more popular use, it has become an aphorism referring to situations analogous to a state of limbo. However, unlike limbo, Schrödinger's cat asks a critical question: when does the uncertainty end, and the cat become one or the other, dead or alive? To the team, Shaw is neither dead nor alive until they know which, leaving her, and them, in an unresolved state which each must reconcile for themselves. Only we, the audience, know which is true.
4. M.I.A. is the acronym for Missing In Action, a military term used to describe troops who cannot be found or have not returned to base after an engagement. In this case, Shaw can be termed M.I.A. because the team cannot determine her whereabouts, or whether she is dead or alive.

Guilty

1. Guest star Blair Brown was a regular cast member of Executive Producer J.J.Abrams previous television series, Fringe.
2. Root, Amy Acker, does not appear in this episode.

Q & A

1. The name of the man with the search anomalies who Anna was investigating, Paul Zimmerman, is similar to the name of noted computer privacy and encryption professional, Phil Zimmerman.

Blunt

1. Bear chews on a Bontoni shoe. Bontoni is an Italian manufacturer of handmade men's shoes; a typical pair costs roughly $1000, and is made to measure.
2. Finch thinks of college life as an overpriced bacchanalia, referring to the Roman festivals of Bacchus, the Greco-Roman god of wine, freedom, intoxication and ecstasy. Finch refers to the common practice that college students, on their own for he first time, drink to excess at dormitory and fraternity parties.
3. Grant University is likely a synonym for Columbia because Grant's tomb is located next to Columbia.

Karma

Skip

Search and Destroy

1. The cigars that Greer has, and says are named after Nepalese warriors are called Gurkhas.
2. Final appearance of Paige Turco as Zoe Morgan. Turco doesn't return for season five due to scheduling conflicts with the third season of The 100 (2014).
3. The suitcase's lock combination of 314 is the first three digits of Pi.
4. People with bipolar disorder tend to be very innovative and productive. With proper treatment and medications they can lead extremely productive lives.

Terra Incognita

1. The title "Terra Incognita" is a Latin phrase meaning, "unknown land".
2. Taraji P. Henson's first appearance as Joss Carter since season 3 episode 9 "The Crossing"
3. The baby picture of Carter and her son Taylor, is a real life picture of Taraji P. Henson and her son Marcel.
4. The "Catskills" is a mountainous resort area located about 3 hours' drive of north of New York city.
5. Harold tells Reese that Bear(the dog) has chewed a first edition Gatsby. Reese says he will buy him another. Harold says he doesn't pay Reese enough to be able to buy another. First edition Gatsby's, in original dust jacket, sell for $100,000 to $150,000.

Asylum

1. The photo showing Samaritan's agent Shelly Spencer in the White House also shows its Analog Interface, Gabriel Hayward, and Senator Ross Garrison in the background. This explains how Gabriel made it into the White House in Person of Interest: Control-Alt-Delete (2015).
2. The sounds that the keypad makes that Root uses to access the room on the 9th floor is the same as the ones used in the movie "WarGames," that Matthew Broderick's character David records to break out of the infirmary.
3. The admitting physician at the hospital was played by John Preston. He is Carrie Preston's brother, and Michael Emerson's brother-in-law.
4. The key code Root uses to access the secure wing (222333) is the same one used in the movie "WarGames" when David is locked into the NORAD medical room.

YHWH

1. The title refers to God's name, written with the Hebrew characters known as the Tetragrammaton, and appears almost 7,000 times in the Old Testament. In Hebrew it is normal to write only consonants, but because of the Commandment against using God's name in vain, correct pronunciation of the name is lost. Name YHWH is preserved in texts but sometimes has added vowel marks from word Adonai, indicating that instead of YHWH one should read Adonai (Lord). English Bibles usually translate it as "Lord of Hosts," or simply as "Lord." One plausible version of OT God's name might be "Yahweh," although some use "Jehovah" instead; that stems from erroneous reading of YHWH with vowels of Adonai.
2. The music during the final download of the A.I. to her local computer while Harold is talking to it, is called 'Welcome to the Machine' from the 1975 Pink Floyd album 'Wish You Were Here'.